RESUMEN
Rapid clinical progress of hepatitis C virus (HCV) replication inhibitors, including these selecting for resistance in the NS5A region (NS5A inhibitors), promises to revolutionize HCV treatment. Herein, we describe our explorations of diverse spiropyrrolidine motifs in novel NS5A inhibitors and a proposed interaction model. We discovered that the 1,4-dioxa-7-azaspiro[4.4]nonane motif in inhibitor 41H (GSK2236805) supported high potency against genotypes 1a and 1b as well as in genotype 1b L31V and Y93H mutants. Consistent with this, 41H potently suppressed HCV RNA in the 20-day RNA reduction assay. Pharmacokinetic and safety data supported further progression of 41H to the clinic.
Asunto(s)
Antivirales/farmacología , Genotipo , Hepacivirus/efectos de los fármacos , Pirrolidinas/farmacología , Compuestos de Espiro/farmacología , Antivirales/química , Antivirales/farmacocinética , Diseño de Fármacos , Hepacivirus/genética , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Modelos Moleculares , Mutación , Pirrolidinas/química , Pirrolidinas/farmacocinética , ARN Viral/sangre , Compuestos de Espiro/química , Compuestos de Espiro/farmacocinéticaRESUMEN
Hepatitis C virus (HCV) assembles many host cellular proteins into unique membranous replication structures as a prerequisite for viral replication, and PI4KIIIα is an essential component of these replication organelles. RNA interference of PI4KIIIα results in a breakdown of this replication complex and cessation of HCV replication in Huh-7 cells. PI4KIIIα is a lipid kinase that interacts with the HCV nonstructural 5A protein (NS5A) and enriches the HCV replication complex with its product, phosphoinositol 4-phosphate (PI4P). Elevated levels of PI4P at the endoplasmic reticulum have been linked to HCV infection in the liver of HCV infected patients. We investigated if small molecule inhibitors of PI4KIIIα could inhibit HCV replication in vitro. The synthesis and structure-activity relationships associated with the biological inhibition of PI4KIIIα and HCV replication are described. These efforts led directly to identification of quinazolinone 28 that displays high selectivity for PI4KIIIα and potently inhibits HCV replication in vitro.
Asunto(s)
1-Fosfatidilinositol 4-Quinasa/antagonistas & inhibidores , Antivirales/farmacología , Inhibidores Enzimáticos/farmacología , Hepacivirus/efectos de los fármacos , Animales , Antivirales/química , Descubrimiento de Drogas , Inhibidores Enzimáticos/química , Hepacivirus/enzimología , Hepacivirus/fisiología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Ratas , Relación Estructura-Actividad , Replicación Viral/efectos de los fármacosRESUMEN
Hyperactive signaling of the MAP kinase pathway resulting from the constitutively active B-Raf(V600E) mutated enzyme has been observed in a number of human tumors, including melanomas. Herein we report the discovery and biological evaluation of GSK2118436, a selective inhibitor of Raf kinases with potent in vitro activity in oncogenic B-Raf-driven melanoma and colorectal carcinoma cells and robust in vivo antitumor and pharmacodynamic activity in mouse models of B-Raf(V600E) human melanoma. GSK2118436 was identified as a development candidate, and early clinical results have shown significant activity in patients with B-Raf mutant melanoma.
RESUMEN
A series of novel, potent 4-aminothienopyridine B-Raf kinase inhibitors was designed and synthesized using knowledge-based design. Compounds 5f, and 6k exhibited not only excellent potency in both enzyme assay (IC(50)=5.1, 16.6 nM) and cellular assay (IC(50)=0.2, 0.2 µM), but also had an outstanding selectivity profile against other kinases.
Asunto(s)
Aminopiridinas/química , Compuestos de Fenilurea/química , Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Tienopiridinas/química , Aminopiridinas/síntesis química , Aminopiridinas/metabolismo , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Compuestos de Fenilurea/síntesis química , Compuestos de Fenilurea/metabolismo , Unión Proteica , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/metabolismo , Proteínas Proto-Oncogénicas B-raf/metabolismo , Relación Estructura-Actividad , Tienopiridinas/síntesis química , Tienopiridinas/metabolismoRESUMEN
Recent results from clinical trials with the BRAF inhibitors GSK2118436 (dabrafenib) and PLX4032 (vemurafenib) have shown encouraging response rates; however, the duration of response has been limited. To identify determinants of acquired resistance to GSK2118436 and strategies to overcome the resistance, we isolated GSK2118436 drug-resistant clones from the A375 BRAF(V600E) and the YUSIT1 BRAF(V600K) melanoma cell lines. These clones also showed reduced sensitivity to the allosteric mitogen-activated protein/extracellular signal-regulated kinase (MEK) inhibitor GSK1120212 (trametinib). Genetic characterization of these clones identified an in-frame deletion in MEK1 (MEK1(K59del)) or NRAS mutation (NRAS(Q61K) and/or NRAS(A146T)) with and without MEK1(P387S) in the BRAF(V600E) background and NRAS(Q61K) in the BRAF(V600K) background. Stable knockdown of NRAS with short hairpin RNA partially restored GSK2118436 sensitivity in mutant NRAS clones, whereas expression of NRAS(Q61K) or NRAS(A146T) in the A375 parental cells decreased sensitivity to GSK2118436. Similarly, expression of MEK1(K59del), but not MEK1(P387S), decreased sensitivity of A375 cells to GSK2118436. The combination of GSK2118436 and GSK1120212 effectively inhibited cell growth, decreased ERK phosphorylation, decreased cyclin D1 protein, and increased p27(kip1) protein in the resistant clones. Moreover, the combination of GSK2118436 or GSK1120212 with the phosphoinositide 3-kinase/mTOR inhibitor GSK2126458 enhanced cell growth inhibition and decreased S6 ribosomal protein phosphorylation in these clones. Our results show that NRAS and/or MEK mutations contribute to BRAF inhibitor resistance in vitro, and the combination of GSK2118436 and GSK1120212 overcomes this resistance. In addition, these resistant clones respond to the combination of GSK2126458 with GSK2118436 or GSK1120212. Clinical trials are ongoing or planned to test these combinations.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Melanoma/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Apoptosis/efectos de los fármacos , Procesos de Crecimiento Celular/efectos de los fármacos , Línea Celular Tumoral , Resistencia a Antineoplásicos , Humanos , Imidazoles/administración & dosificación , Imidazoles/farmacología , Indoles/administración & dosificación , Indoles/farmacología , MAP Quinasa Quinasa 1/antagonistas & inhibidores , Melanoma/enzimología , Oximas/administración & dosificación , Oximas/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosforilación , Inhibidores de Proteínas Quinasas/administración & dosificación , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Sulfonamidas/administración & dosificación , Sulfonamidas/farmacología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , VemurafenibRESUMEN
A potent series of inhibitors against the B-Raf(V600E) kinase have been developed that show excellent activity in cellular assays and good oral bioavailability in rats. The key structural features of the series are an arylsulfonamide headgroup, a thiazole core, and a fluorine ortho to the sulfonamide nitrogen.
Asunto(s)
Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Sulfonamidas/química , Administración Oral , Sustitución de Aminoácidos , Animales , Sitios de Unión , Dominio Catalítico , Flúor/química , Microsomas Hepáticos/metabolismo , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacocinética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Ratas , Relación Estructura-ActividadRESUMEN
We report the synthesis and in vitro activity of a series of novel N-{3-[(1,1-dioxido-1,2-benzothiazol-3-yl)(phenyl)amino]propyl}benzamide analogs. These analogs showed potent inhibitory activity against Kv1.3. Several compounds, including compound 8b, showed similar potency to the known Kv1.3 inhibitor PAP-1 when tested under the IonWorks patch clamp assay conditions.
Asunto(s)
Benzamidas/química , Benzotiazoles/química , Canal de Potasio Kv1.3/antagonistas & inhibidores , Amidas , Animales , Benzamidas/farmacología , Benzotiazoles/farmacología , Línea Celular , Humanos , Proteínas Asociadas a Pancreatitis , Técnicas de Placa-Clamp , Relación Estructura-Actividad , Sulfonamidas , Urea/análogos & derivadosRESUMEN
We report the synthesis and in vitro activity of a series of novel substituted N-{3-[(1,1-dioxido-1,2-benzothiazol-3-yl)(phenyl)amino]propyl}benzamide analogs. These analogs showed potent inhibitory activity against Kv1.3. Several demonstrated similar potency to the known Kv1.3 inhibitor PAP-1 when tested under the IonWorks patch clamp assay conditions. Two compounds 13i and 13rr were advanced further as potential tool compounds for in vivo validation studies.
Asunto(s)
Benzamidas/química , Benzamidas/farmacología , Benzotiazoles/química , Canal de Potasio Kv1.3/antagonistas & inhibidores , Amidas , Animales , Benzotiazoles/farmacología , Línea Celular , Humanos , Proteínas Asociadas a Pancreatitis , Técnicas de Placa-Clamp , Ratas , Relación Estructura-ActividadRESUMEN
Aniline 'headgroups' were synthesized and incorporated into an alkynyl thienopyrimidine series of EGFR and ErbB-2 inhibitors. Potent inhibition of enzyme activity and cellular proliferation was observed. In certain instances, protein binding was reduced and oral exposure was found to be somewhat improved relative to compounds containing the reference aniline.
Asunto(s)
Compuestos de Anilina/síntesis química , Receptores ErbB/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/síntesis química , Pirimidinas/síntesis química , Receptor ErbB-2/antagonistas & inhibidores , Administración Oral , Compuestos de Anilina/administración & dosificación , Compuestos de Anilina/farmacología , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos/métodos , Receptores ErbB/metabolismo , Inhibidores de Crecimiento/administración & dosificación , Inhibidores de Crecimiento/síntesis química , Inhibidores de Crecimiento/farmacología , Humanos , Ratones , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/administración & dosificación , Pirimidinas/farmacología , Receptor ErbB-2/metabolismoRESUMEN
Key binding interactions of the anthranilimide based glycogen phosphorylase a (GPa) inhibitor 2 from X-ray crystallography studies are described. This series of compounds bind to the AMP site of GP. Using the binding information the core and the phenyl urea moieties were optimized. This work culminated in the identification of compounds with single nanomolar potency as well as in vivo efficacy in a diabetic model.